From Nookipedia, the Animal Crossing wiki
Uchi villagers are a type of female characters in Animal Crossing: New Leaf. The Japanese word "Uchi" refers to the personal pronoun these characters use in the Japanese version. Sometimes called the "Big Sister" personality, it is similar to the Snooty personality in previous Animal Crossing games, but the villagers display a more caring and less vain personality. They end their talking usually with their catchphrase. They wake up at 11:00 AM and go to bed at 3:00 AM.
They are also seen as the game's version of a Tomboy, as they occasionally talk about enjoying fighting, and interest in participating in 'turf wars'. In addition to this they might give the player a petition called 'Tomboys Are People Too' which further supports this. They are the female equivalent to the male smug villagers.
Below are some (not all) quotes made by uchi villagers.